Pituitary Pars Intermedia Dysfunction (PPID) in Horses
Authors: Kirkwood Naomi C., Hughes Kristopher J., Stewart Allison J.
Journal: Veterinary Sciences
Summary
# Editorial Summary: Pituitary Pars Intermedia Dysfunction in Horses PPID remains a significantly underrecognised condition despite its considerable impact on equine health and welfare, with both owners and veterinarians frequently underestimating its clinical importance. Kirkwood and colleagues comprehensively review the clinical presentation, underlying pathophysiology, available diagnostic approaches, and current treatment protocols, emphasising that early recognition and diagnosis are critical to improving affected horses' quality of life. Current diagnostic limitations are substantial: basal ACTH concentrations lack adequate sensitivity for reliable detection, whilst the TRH stimulation test—considered more diagnostically robust—is hampered by commercial unavailability as a registered sterile product in many countries, creating significant practical barriers to accurate diagnosis. The authors identify several priority areas for future research, particularly the complex relationship between PPID and insulin dysregulation and their combined role in laminitis development, alongside the need for better data on long-term pergolide efficacy and optimal management strategies. For equine practitioners, this review underscores the importance of maintaining a high index of suspicion for PPID in ageing horses and advocating for improved diagnostic tools and protocols to enable earlier intervention and better client education regarding prognosis and management outcomes.
Read the full abstract on the publisher's site
Practical Takeaways
- •Increase vigilance for early PPID signs in your patients—early diagnosis and treatment initiation significantly improves quality of life and outcomes
- •Be aware that basal ACTH testing alone may miss cases; consider TRH stimulation testing where available and combine with clinical assessment for better diagnostic accuracy
- •Recognize PPID as a systemic endocrine condition linked to insulin dysregulation and laminitis; manage metabolic comorbidities alongside pergolide therapy
Key Findings
- •PPID morbidity is often underestimated by owners and veterinarians, highlighting a recognition gap in clinical practice
- •Basal ACTH concentration lacks sufficient sensitivity for reliable PPID diagnosis
- •TRH stimulation testing is limited by unavailability of commercially sterile registered products in many countries
- •Strong association exists between PPID and insulin dysregulation with subsequent laminitis risk